The linux-2.6 and user-mode-linux upgrades from DSA-2303-1 has caused aregression that can result in an oops during invalid accesses to/proc//maps files.

The text of the original advisory is reproduced for reference:

Several vulnerabilities have been discovered in the Linux kernel that may leadto a denial of service or privilege escalation. The Common Vulnerabilities andExposures project identifies the following problems:

CVE-2011-1020

Kees Cook discovered an issue in the /proc filesystem that allows local users to gain access to sensitive process information after execution of a setuid binary.

CVE-2011-1576

Ryan Sweat discovered an issue in the VLAN implementation. Local users may be able to cause a kernel memory leak, resulting in a denial of service.

CVE-2011-2484

Vasiliy Kulikov of Openwall discovered that the number of exit handlers that a process can register is not capped, resulting in local denial of service through resource exhaustion (cpu time and memory).

CVE-2011-2491

Vasily Averin discovered an issue with the NFS locking implementation. A malicious NFS server can cause a client to hang indefinitely in an unlock call.

CVE-2011-2492

Marek Kroemeke and Filip Palian discovered that uninitialized struct elements in the Bluetooth subsystem could lead to a leak of sensitive kernel memory through leaked stack memory.

CVE-2011-2495

Vasiliy Kulikov of Openwall discovered that the io file of a process' proc directory was world-readable, resulting in local information disclosure of information such as password lengths.

CVE-2011-2496

Robert Swiecki discovered that mremap() could be abused for local denial of service by triggering a BUG_ON assert.

CVE-2011-2497

Dan Rosenberg discovered an integer underflow in the Bluetooth subsystem, which could lead to denial of service or privilege escalation.

CVE-2011-2517

It was discovered that the netlink-based wireless configuration interface performed insufficient length validation when parsing SSIDs, resulting in buffer overflows. Local users with the CAP_NET_ADMIN capability can cause a denial of service.

CVE-2011-2525

Ben Pfaff reported an issue in the network scheduling code. A local user could cause a denial of service (NULL pointer dereference) by sending a specially crafted netlink message.

CVE-2011-2700

Mauro Carvalho Chehab of Red Hat reported a buffer overflow issue in the driver for the Si4713 FM Radio Transmitter driver used by N900 devices. Local users could exploit this issue to cause a denial of service or potentially gain elevated privileges.

CVE-2011-2723

Brent Meshier reported an issue in the GRO (generic receive offload) implementation. This can be exploited by remote users to create a denial of service (system crash) in certain network device configurations.

CVE-2011-2905

Christian Ohm discovered that the 'perf' analysis tool searches for its config files in the current working directory. This could lead to denial of service or potential privilege escalation if a user with elevated privileges is tricked into running 'perf' in a directory under the control of the attacker.

CVE-2011-2909

Vasiliy Kulikov of Openwall discovered that a programming error in the Comedi driver could lead to the information disclosure through leaked stack memory.

CVE-2011-2918

Vince Weaver discovered that incorrect handling of software event overflows in the 'perf' analysis tool could lead to local denial of service.

CVE-2011-2928

Timo Warns discovered that insufficient validation of Be filesystem images could lead to local denial of service if a malformed filesystem image is mounted.

CVE-2011-3188

Dan Kaminsky reported a weakness of the sequence number generation in the TCP protocol implementation. This can be used by remote attackers to inject packets into an active session.

CVE-2011-3191

Darren Lavender reported an issue in the Common Internet File System (CIFS). A malicious file server could cause memory corruption leading to a denial of service.

This update also includes a fix for a regression introduced with the previoussecurity fix for CVE-2011-1768 (Debian: #633738)

For the stable distribution (squeeze), this problem has been fixed in version2.6.32-35squeeze2. Updates for issues impacting the oldstable distribution(lenny) will be available soon.

The following matrix lists additional source packages that were rebuilt forcompatibility with or to take advantage of this update:

Debian 6.0 (squeeze) user-mode-linux 2.6.32-1um-4+35squeeze2

We recommend that you upgrade your linux-2.6 and user-mode-linux packages.

Further information about Debian Security Advisories, how to applythese updates to your system and frequently asked questions can befound at: http://www.debian.org/security/